<!doctype html>
<html>

<head>
    <title>Line Chart</title>
    <script src="../dist/Chart.bundle.js"></script>
    <script src="http://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
    <style>
        canvas {
            -moz-user-select: none;
            -webkit-user-select: none;
            -ms-user-select: none;
        }
    </style>
</head>

<body>
    <div style="width:75%;">
        <canvas id="canvas"></canvas>
    </div>
    <br>
    <br>
    <button id="randomizeData">Randomize Data</button>
    <button id="addData">Add Data</button>
    <button id="removeData">Remove Data</button>
    <script>
        var MONTHS = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];
        var randomScalingFactor = function() {
            return Math.round(Math.random() * 100 * (Math.random() > 0.5 ? -1 : 1));
        };
        var randomColorFactor = function() {
            return Math.round(Math.random() * 255);
        };
        var randomColor = function(opacity) {
            return 'rgba(' + randomColorFactor() + ',' + randomColorFactor() + ',' + randomColorFactor() + ',' + (opacity || '.3') + ')';
        };

        var config = {
            type: 'line',
            data: {
                labels: ["January", "February", "March", "April", "May", "June", "July"],
                datasets: [{
                    label: "dataset - big points",
                    data: [randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor()],
                    fill: false,
                    borderDash: [5, 5],
                    pointRadius: 15,
                    pointHoverRadius: 10,
                }, {
                    label: "dataset - individual point sizes",
                    data: [randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor()],
                    fill: false,
                    borderDash: [5, 5],
                    pointRadius: [2, 4, 6, 18, 0, 12, 20],
                }, {
                    label: "dataset - large pointHoverRadius",
                    data: [randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor()],
                    fill: false,
                    pointHoverRadius: 30,
                }, {
                    label: "dataset - large pointHitRadius",
                    data: [randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor(), randomScalingFactor()],
                    fill: false,
                    pointHitRadius: 20,
                }]
            },
            options: {
                responsive: true,
                legend: {
                    position: 'bottom',
                },
                hover: {
                    mode: 'label'
                },
                scales: {
                    xAxes: [{
                        display: true,
                        scaleLabel: {
                            display: true,
                            labelString: 'Month'
                        }
                    }],
                    yAxes: [{
                        display: true,
                        scaleLabel: {
                            display: true,
                            labelString: 'Value'
                        }
                    }]
                },
                title: {
                    display: true,
                    text: 'Chart.js Line Chart - Different point sizes'
                }
            }
        };

        $.each(config.data.datasets, function(i, dataset) {
            var background = randomColor(0.5);
            dataset.borderColor = background;
            dataset.backgroundColor = background;
            dataset.pointBorderColor = background;
            dataset.pointBackgroundColor = background;
            dataset.pointBorderWidth = 1;
        });

        window.onload = function() {
            var ctx = document.getElementById("canvas").getContext("2d");
            window.myLine = new Chart(ctx, config);
        };

        $('#randomizeData').click(function() {
            $.each(config.data.datasets, function(i, dataset) {
                dataset.data = dataset.data.map(function() {
                    return randomScalingFactor();
                });

            });

            window.myLine.update();
        });

        $('#addData').click(function() {
            if (config.data.datasets.length > 0) {
                var month = MONTHS[config.data.labels.length % MONTHS.length];
                config.data.labels.push(month);

                $.each(config.data.datasets, function(i, dataset) {
                    dataset.data.push(randomScalingFactor());
                    if (Array.isArray(dataset.pointRadius)) {
                      dataset.pointRadius.push(Math.random() * 30);
                    }
                });

                window.myLine.update();
            }
        });

        $('#removeData').click(function() {
            config.data.labels.splice(-1, 1); // remove the label first

            config.data.datasets.forEach(function(dataset, datasetIndex) {
                dataset.data.pop();
                if (Array.isArray(dataset.pointRadius)) {
                  dataset.pointRadius.pop();
                }
            });

            window.myLine.update();
        });
    </script>
</body>

</html>
